Doug Thompson, 64, stands on the deck of the “Dana Pride,” scanning the steely blue waters off the coast of Dana Point, Calif. (pop. 33,351), for the telltale spray of gray whales surfacing to breathe.

“We’re out here with one of the most ancient animals on the planet,” says Thompson, leading an afternoon whale-watching tour aboard the 95-foot vessel.

The thrill of spotting the massive marine mammals—sometimes close enough to see the barnacles on their backs or sides—draws thousands of people to Dana Point each year. Whale watchers scan the ocean for signs of movement and alert each other when they see a spout of steam rising above the waves.

Whale watching long has been a popular pastime along the Pacific Coast. In fact, Dana Point’s namesake, Richard Henry Dana Jr., wrote about observing the giant sea creatures in his book “Two Years Before the Mast,” in which the Harvard law student-turned-seaman chronicled his 1834 voyage from Boston to California.

Each March, Dana Point residents pay tribute to Dana by reading his entire book aloud during the Festival of Whales. The festival also features a parade, marine mammal lectures, sand sculpting workshops and, of course, whale-watching cruises.

“We were the first ones to offer whale-watching tours in California,” says Don Hansen, 77, owner of Dana Wharf Sportfishing, which operates the “Dana Pride.”

Hansen started the festival with local historian Doris Walker in 1971 to entice visitors to Dana Point Harbor and the Ocean Institute, which promotes ocean stewardship through marine science, environmental and maritime history programs.

The festival coincides with the annual whale migration. Each spring, hundreds of gray whales—measuring up to 50 feet long and weighing up to 36 tons—skirt the California coast en route to their summer feeding grounds in the Arctic Ocean. Come autumn, they return to the warm waters off Baja California, where they mate, and where already-pregnant females birth their calves.

Though gray whales are the focal point of the festival, sightseers also might see pods of bottlenose or common dolphins; fin or humpback whales; and California sea lions during a whale-watching excursion.

Dana Point, incorporated 18 years after its first whale festival, also reveres the long-ago sailor who wrote about “calling out ‘there she blows!’” each time a whale spouted along California’s coast and described the beauty of the city’s most prominent natural landmark, a steep hill towering above the Pacific Ocean.

In his 1840 book, Dana dubbed the coastal bluff—then called San Juan Point for the nearby Mission San Juan Capistrano—“the only romantic spot in California.” Dana also detailed how he and his shipmates tossed dried cowhides—one at a time—off the 200-foot-high cliff. Below, seamen gathered the stiff hides and loaded them aboard the “Pilgrim” for transport back to Boston.

Like Dana, the migrating whales may place great significance on the prominent bluff, now called the Headlands. Whale researchers theorize that the Headlands may serve as a landmark that helps gray whales navigate on their 10,000-mile-roundtrip migration.

“This animal has endured sailing ships that have hunted it, and it’s still going up and down our coast,” says Todd Mansur, 46, a veteran whale-watching guide and Dana Point native. “It’s amazing.”